First off, I want to thank everyone in this community. You helped me practice and learn. You taught me how to turn my ugly 80-line code into a beatiful yet unreadable one liner(JK, I never learned that). I couldn't do this without you.

Timeline

8/10 - Applied
9/14 - OA 1
9/17 - OA 2
9/20 - I received an email saying Amazon is not moving forward with my application
9/21 - I received another email saying "Oops, that was a mistake. Please finish OA 3."
9/25 - OA 3
9/30 - Invite to virtual onsite
10/14 - onsite, 3 rounds 45 mins each
10/19 - portal status changed - moved to another job
10/20 - offer letter

Preparation

I mainly focused on questions mentioned in this post.
https://leetcode.com/discuss/interview-question/488887/Amazon-Final-Interview-Questions-or-SDE1

Youtube has some pretty good resources on how to answer LP questions.

• Dan Croitor
• Holly Lee

My tips are:

• You should introduce yourself in a way which leads the interviewer to ask about one of your projects(which you will heavily prepare to talk about).
• Prepare to answer every possible behavioral question in the context of that one project.
• Prepare at least 2 examples for each leadership principle. Some stories can apply to more than just one LP. These don't have to be coding related stories!
• Practice telling the stories out loud! Paint a picture, don't read off of your note.
• I wrote down 10 questions to ask the interviewers. I felt like I needed more.
• Be confident! Talk about the challenges with passion, focus on how you made it work, be proud of your results!

The OA experience and my self reflection

• I did poorly on OA 1. It was not hard but I was definitely too slow. Tip here is don't read the prompt if you are slow like me, the function sigunature is telling you exactly what it does in less than 5 words. I think I solved 3 out of 7 debugging questions.
• I did horribly on OA 2. For the first question I only passed 2 test cases that were shown to me. For the second question, there were "unhandled exception thrown". So I passed 0 test case and I still don't know what happened there(Not time limit exception, it didn't even pass the unhidden happy test cases).
• I honestly was not surprised when they sent me the rejection letter, given how horrible I felt after OA 1 and 2.
• I highly suspect there were errors in my OA 2 questions, hence they decided to let me move on with the process after reviewing my code for OA 2.
• OA 3 was work simulation. I studied LP and felt good about it.

Onsite

• First round is with a SDE manager, she jumped right in, no self introduction. Why Amazon? Why switch career path(I was an accountant for a year)? She was really interested in my internship project. We went into great details and spent almost 15 minutes talking about it. I had 20 minutes left for the technical question. I talked about my first approach(which was wrong). She gave me another example to consider and walked through it with me. I quickly got the hint and worked on implementing. I noticed a mistake she made while she was walking me through, and I think catching that saved me in this interview.
• Second round, interviewer was late for 5 minutes which made it really tight. She asked 2 most frequently asked behavioral questions and moved on to coding question. I asked her clarification questions. Coded it in python, and explained how python list can contain different types of object made the question slightly easier to solve. Of course talked about time and space complexity.
• Third round had really good flow. I repeated the story of my internship project and showed the interviewer a 2 minute presentation of the project(Yes I made a powerpoint to show off my project, because for this specific project I know having the visual makes a bigger impact). He seemed to be very impressed. The design question I actually saw in someone else's post the day before my onsite, I got lucky. He really pushed hard for better design, more flexibility with the follow up questions. I talked about OOD principles that are used to make a better/more flexible design.
• After the interviews, I sent all of them a thank you note.

Hope this helps. Good luck!